Abstract: A Doppler radar sensor with a power detector is disclosed. In the Doppler radar sensor, a power detector is provided to detect the power level of a received transmission signal, and a leakage and clutter canceler is provided to generate a cancellation signal according to the power level of the received transmission signal. The cancellation signal is used to cancel leakage and clutter in the received transmission signal such that object displacement in the received transmission signal can be identified.

Abstract: In a life detection method of the present invention, a signal transceiver is configured to transmit a transmission signal to an area and receive a reflected signal from the area as a detection signal, a demodulator coupled to the signal transceiver is configured to receive and demodulate the detection signal to output a demodulated signal, a compute element coupled to the demodulator is configured to receive the demodulated signal and compute a RMS value of the demodulated signal, and a determination element coupled to the compute element is configured to receive the RMS value of the demodulated signal and determine whether having a living body within the area according to the RMS value and a RMS threshold value.

Abstract: A Doppler radar sensor includes a radar and a bondwire interconnection. The bondwire interconnection is connected to a signal generator and an antenna of the radar and configured to transmit a radio frequency signal generated by the signal generator to the antenna and transmit a reflected signal received by the antenna to a demodulator of the radar. A metal strip, a first shunt bondwire and a second shunt bondwire of the bondwire interconnection can be used as a matching circuit of the antenna to decrease the transmission loss and increase the detection distance of the radar.

Abstract: In a noncontact self-injection-locked sensor, a self-injection-locked oscillating integrated antenna is designed to radiate a signal to a subject and be injection-locked by a reflect signal reflected from the subject. Owing to the reflect signal is phase-modulated by vital signs of the subject, a demodulator is provided to demodulate an injection-locked signal of the self-injection-locked oscillating integrated antenna to obtain a vital signal of the subject.

Abstract: By changing frequencies of an oscillation signal and an injection signal, a frequency-converted self-injection-locked radar has an oscillation frequency different to a frequency of a transmitted signal from a transceiver antenna element such that the frequency-converted self-injection-locked radar with high sensitivity and penetration or with high sensitivity d low cost is achieved.